Antenna connector



July 13, 1943 R. E. Kx-:sTER ETAL 2,444,934

ANTENNA CONNECTOR Filed June 9, 1944 /l//l/ A El! lll/lll INVENTOR. ROBERT E. KESTER BY HENRY R.SM|TH HTTO/PA/EY I Patented July 13, 1948 OFFICE ANTENNA CONNECTOR Robert E. Kester and Henry R. Smith, Dayton, Ohio Application June 9, 1944, Serial No. 539,564

2` Claims.

(Granted under amended April The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon.

The invention to be hereinafter described relates to antenna connector clamps.

It is common and well known practice, in the use of radio equipment in planes to project or extend wire antenna through the bottom or underside oi the plane. Such antenna conductors are the usual copper wire type and are reeled in and out according to circumstance to the proper length according to existing conditions. In use there is bound to be a great deal of whipping about of the antenna relative to its outlet guide due to the plane night with resulting destructive wear. The sudden and severe bending stresses involved during such violent whipping action are additionally highly destructive. But an even more important objection to many present antenna connector clamps is that they must be loosened or adjusted or even disconnected to permit reeling of the antenna, either in or out. In order to maintain operative position of the antenna, as well known, the lower or free end must be heavily weighted, a small, compact hook being inserted between the antenna end and the weight. Any such connecting device on or in the antenna is an added difficulty with such clamps. Frequently, an antenna is broken or damaged and what remains must be completely reeled in for repair or renewal. The reeling in and out may be very frequent in any given length of time according to circumstances, conditions and requirements of use. The softness of the copper wire antenna passing through clamps of copper, aluminum, or silver causes much higher friction and corresponding wear than it does passing through or over polished stainless steel and, of course, stainless steel is also corrosion resistant. Heretofore, such clamps have been made of the better conducting materials such as silver, aluminum, and copper which wear readily, cause greater wear of the antenna and give a poorer contact.

The present invention eliminates the above and other objections of known types of clamps used for the same purpose and provides a simple, efficient compact and low cost clamp through which the antenna may be reeled in or out without interruption to change or operate the clamp. At the same time, it reduces to the minimum all destructive action and wear on the antenna and provides greater improved contact between antenna and clamp.

the act of March 3, 1883, as

In order to more clearly disclose the construction, operation and use of the invention reference should be had to the accompanying drawings forming part of the present application. Throughout the several figures of the drawings like reference characters designate the same parts in the different views.

In the drawings:

Fig. 1 is a perspective view of an antenna connector clamp embodying the present invention shown as assembled with an otherwise conventional antenna guide tube and associated parts;

Fig. 2 is Ian enlarged elevation of the clamp, and part of the guide tube of Figure 1:

Fig. 3 is a plan view of Fig. 2; and

Fig. 4 is a cross section of Fig. 3, taken along line 4 4, with the terminal removed.

Referring to the drawings in detail, I indicates the clamp as a whole. As shown, it is of generally cylindrical shape, though that is not essential. For an appreciable length, from one end, the clamp is split as at 2 and provided with the usual tightening screw or bolt 3 by which the clamp end may be tightened on or secured to the end of the usual iibre antenna guide tube 4. Secured in operative position within the clamp I is a bell or funnel shaped centering antenna guide 5 of polished stainless steel. As shown, the outer diameter of said antenna guide 5 is `substantially that of the inside diameter of the clamp, whereas the inner diameter is slightly less than that of the inner diameter of the fibre tube. This guide, as shown, is located at the inner end of tube II and its outer edge seats ber tween spaced ribs, upsets formed by punch, or

the like, on the inner wall of I.

Within the body oi the clamp I are disposed two antenna guiding plates having contact surfaces l and E, respectively. These surfaces or plates may be secured in place in any suitable manner such as by welding or soldering or they may be removably secured in place in any one of a number of ways well known to those skilled in the art. These surfaces are shown as rounded or circular in contour, the curvature extending lengthwise of the body of clamp I and, therefore, in the direction of movement of the antenna 9 through the clamp and over surfaces 'I and 8. They also extend completely across the interior of I, laterally, providing a continu ous surface from side to side but curved in the direction of the length of the clamp body. Guide surfaces l and 8 are spaced apart appreciably, lengthwise of clamp body I, so that an antenna may pass readily from one to the other. They are disposed almost, but not quite, diametrically of the clamp I. The one nearest the end has its contact surface just slightly above the diameter while that remote from the end is just slightly below. The result of this arrangement is that the antenna wire 9 passing through clamp I to or from the reel, mounted in usual and well known manner in the plane, will be slightly deflected by those surfaces, as shown in Figure 4. Due to the weight on the free end of the antenna, there will be :appreciable pressure between the antenna land surfaces 'I and 8.

Due to the polished stainless steel surfaces of 'I and 8, their arrangement very close to either side of the center of clamp I, their spacing lengthwise of clamp I, and the tension of the antenna 9 maintained by the usual weight, a uniform, continuous, wiping contact is maintained at all times between antenna 9 and surfaces I and 8. This contact is much more uniform and constant than where other materials or other constructions have been used. Because the antenna 9 is free t0 move laterally the full diameter of tube I across the full length of surfaces I and 8, all sharp twisting or bending oi" it is completely eliminated.

Contact is continuously maintained at all times between the antenna and clamp I, whether the antenna is being fed out or reeled in, yet there is no need at any time to disconnect the clamp from the antenna or even to loosen it. There is a slid'- ing contact under slight predetermined pressure.

The small hook or like means I 0 for connecting the usualweight to the antenna en-d may easily pass freely over surfaces 'I and 8 and through` the clamp. So an old antenna or the remains of one may be easily withdrawn right through the clamp Y and a new one as readily inserted through it in the opposite direction. The mounting of the reel within the plane and its positions or locations relative to the inner end of the tube 4 and clamp I are well understood and not considered either necessary or desirable to illustrate in this case.

The plane transmitters output terminal, indicated diagrammatically at Il, may be connected through conductor I 2 to the terminal I3, of usual and well known type on clamp I.

While a cylindrical form of the invention has been illustrated. it will be understood that various other forms may be used provided they embody the relative disposition and combination of the respective features as disclosed.

It is 4believed that the construction, operation and use of the invention will be clear from the preceding detailed description wherein one preferred form has been set forth by way of illustration and with no thought or intention of in any degree limiting the invention thereby. It is meant to include all such within this application.

Having thus described our invention, what we claim and desire to protect by Letters Patent is:

1 An antenna connector clamp comprising a tubular body and two stationary plates secured within said tube, said plates being spaced apart longitudinally of said tube, extending laterally completely across the interior of said tube and presenting oppositely disposed convex bearing surfaces extending longitudinally of said tubular body at different levels, said plates and tubular body being of electrically conductive material, and a centering funnel-shaped antenna guide secured conoentrically within said tube between the innermost of the aforesaid plates and the adjaend of the tubular body.

2. An antenna connector clamp comprising a metallic tubular member, a metallic antenna guide plate mountedwithin and across said member, said plate having a smooth curved surface which is a section of a cylindroid, a similar mctallic plate mounted across said member and spaced from the first plate with the curved surfaces of said plates facing in opposite directions, the longitudinal axes of said surfaces being substantially horizontal, parallel to each other, and normal to the axis of the member, one of said surfaces extending below and the other above said member axis to such an, extent that, when the antenna is under operating tension, it makes a positive wiping electrical Contact with said plates, and a funnel shaped centering guide mounted across the distal end of said member.

ROBERT E, KESTER. HENRY R. SMITH.

REFERENCES CITED The following references are ol` .reuord in the ille of this patent:

Number Name Date 1,346,539 Gray July 13, 1920 1,456,178 Crockett May 22, 1923 2,188,062 Schroder Jan. 23, 1940 2,251,418 Pavlik Aug. 5, 1941 FOREGN PATENTS Number Co unt-ry Da te 425,764 Great Britain Mar. 21, 1935 

